如何将图像文件从库移动到另一个文件夹

Question

我想从图库中获取图像并将其保存到另一个文件夹。我尝试使用代码

// ! UNCOMMENT THIS IF YOU RATHER WANT TO USE THE LINERENDERER !
//#define USE_LINERENDERER

using UnityEngine;
using UnityEngine.UI;

[RequireComponent(typeof(MeshFilter))]
[RequireComponent(typeof(MeshRenderer))]
public class PlaneController : MonoBehaviour
{
    [Header("Input")]

    // Reference these in the Inspector
    public Transform target1;
    public Transform target2;
    public Transform target3;
    public Transform target4;

    [Space]

    public MeshFilter meshFilter;

    [Header("Output")]
    public float AngleOnPlane;

    public Text angleText;
    public float lineWith = 0.05f;

#if USE_LINERENDERER
    public LineRenderer lineRenderer;
#else
    public MeshRenderer cubeLine;
#endif

    private Mesh mesh;
    private Vector3[] vertices;
    private Vector3 redLineDirection;

    // if using line renderer
    private Vector3[] positions = new Vector3[2];

    private void Start()
    {
        InitializePlaneMesh();

#if USE_LINERENDERER
        InitializeLineRenderer();
#endif
    }

    // Update is called once per frame
    private void Update()
    {
        // update the plane mesh
        UpdatePlaneMesh();

        // update the angle value
        UpdateAngle();
#if USE_LINERENDERER
        // update the line either using the line renderer
        UpdateLineUsingLineRenderer();
#else
        // update the line rather using a simple scaled cube instead
        UpdateLineUsingCube();
#endif
    }

    private void InitializePlaneMesh()
    {
        if (!meshFilter) meshFilter = GetComponent<MeshFilter>();

        mesh = meshFilter.mesh;

        vertices = new Vector3[4];

        // Set the 4 triangles (front and backside)
        // using the 4 vertices
        var triangles = new int[3 * 4];

        // triangle 1 - ABC
        triangles[0] = 0;
        triangles[1] = 1;
        triangles[2] = 2;
        // triangle 2 - ACD
        triangles[3] = 0;
        triangles[4] = 2;
        triangles[5] = 3;

        // triangle 3 - BAC
        triangles[6] = 1;
        triangles[7] = 0;
        triangles[8] = 2;
        // triangle 4 - ADC
        triangles[9] = 0;
        triangles[10] = 3;
        triangles[11] = 2;

        mesh.vertices = vertices;
        mesh.triangles = triangles;
    }

#if USE_LINERENDERER
    private void InitializeLineRenderer()
    {
        lineRenderer.positionCount = 2;
        lineRenderer.startWidth = lineWith;
        lineRenderer.endWidth = lineWith;
        lineRenderer.loop = false;
        lineRenderer.alignment = LineAlignment.View;
        lineRenderer.useWorldSpace = true;
    }
#endif

    private void UpdatePlaneMesh()
    {
        // build triangles according to target positions
        vertices[0] = target1.position - transform.position; // A
        vertices[1] = target2.position - transform.position; // B
        vertices[2] = target3.position - transform.position; // C

        // D = A  + B->C
        vertices[3] = vertices[0] + (vertices[2] - vertices[1]);

        // update the mesh vertex positions
        mesh.vertices = vertices;

        // Has to be done in order to update the bounding box culling
        mesh.RecalculateBounds();
    }

    private void UpdateAngle()
    {
        // get the plane (green line/area)
        var plane = new Plane(target1.position, target2.position, target3.position);

        // get the red vector
        redLineDirection = target4.position - target1.position;

        // get difference
        var angle = Vector3.Angle(plane.normal, redLineDirection);

        // since the normal itself stands 90° on the plane
        AngleOnPlane = Mathf.Abs(90 - angle);

        // write the angle value to a UI Text element
        angleText.text = $"Impact Angle = {AngleOnPlane:F1}°";

        // move text to center of red line and a bit above it
        angleText.transform.position = (target1.position + target4.position) / 2f + Vector3.up * 0.1f;

        // make text always face the user (Billboard)
        // using Camera.main here is not efficient! Just for the demo
        angleText.transform.forward = Camera.main.transform.forward;
    }

#if USE_LINERENDERER
    private void UpdateLineUsingLineRenderer()
    {
        positions[0] = target1.position;
        positions[1] = target4.position;

        lineRenderer.SetPositions(positions);
    }
#else
    private void UpdateLineUsingCube()
    {
        // simply rotate the cube so it is facing in the line direction
        cubeLine.transform.forward = redLineDirection.normalized;

        // scale it to match both target positions with its ends
        cubeLine.transform.localScale = new Vector3(lineWith, lineWith, redLineDirection.magnitude);

        // and move it to the center between both targets
        cubeLine.transform.position = (target1.position + target4.position) / 2f;
    }
#endif
}

Answer 1

我建议使用try-with-resources和Java 8文件/路径api：

private void copyFile(File inputPath, File outputPath){
 try (FileOutputStream fos = new FileOutputStream(outputPath)) {

     Files.copy(inputPath.toPath(), fos);
     Log.d("Copied file to ", outputPath.toString());

  } catch (FileNotFoundException fnfe1) {
     Log.d("Tag",fnfe1.getMessage());
  } catch (Exception e) {
     Log.d("tag", e.getMessage());
  }
}